## Thursday, 14 February 2013

### How tall is your class?

Well, a new year, a new class, a new grade. What new adventures will befall us?

This year I have moved up to the big kids - Year 6!

And like a lot of teachers I suppose, we on Year 6 decided that it might be good to start the year with a review of number skills.

And the first one we chose was addition.

So, how can you do an inquiry into a review of addition?

Our year group was starting the year with an inquiry into the transdisciplinary theme of "Who We Are", focusing on the physical, mental and social changes of adolescence.

As part of our exploration of physical change, I thought we could measure the combined heights of all the students in the class, then compare each class to see which was tallest.

This would involve lots of addition.

And some mathematical thinking.

Then if we repeat the process in about 6 or 7 weeks, we can see if there has been any change. Maybe we could even do it again at the end of the year.

## Tuning In With Some Basic Addition

We started our brains up, or began the tuning in, with a 10 minute challenge. Students were provided with a series of questions that focused on addition skills:

i) What do I need to add to these numbers to get to 50?
ii) What do I need to add to these numbers to get to 100?
iv) Simple word problems involving addition of 2-digit numbers

In days gone by, this would have been the end of my maths lesson - do a page of algorithms - mission accomplished.

I still use this type of material - and the questions we used were from a textbook - but it is as a starting point for further investigation, not as an end in itself.

## Thinking Mathematically

Now our brains were engaged and our skills were tuned in, we began the "finding out" part of the inquiry.

I asked the kids to list questions that they would need to answer in order to direct their inquiry.

Here's a few of the questions they came up with:
• How many people are in our class?
• How many classes are we comparing ourselves to?
• How tall is each person?
• What is the average height of each person in our class?
• How can we make it a fair comparison between classes?

## Methodology

So, how were we going to measure the height of a class?

Well, the kids came up with three suggestions:

1. We all stand on each others shoulders and then hold a tape measure up to see how tall we are

2. We all lie on the ground in a long line and use a tape measure to see how long the line is

3. We measure each individual and then add them together

We took a vote and decided on Option #3 so we all got to measure each other and came up with a total (well, we came up with several totals and then needed to go back and check that we were measuring accurately and adding correctly).

Our total was 3637cm.

How we measured the height of our partner

Sorting it all out in a table

And so that we didn't miss out on the fun, and also so that we could try out another methodology, we all went outside and lay down on the grass and used Option #2.

Yes! Looks like 6BF is taller than 6TL

Rolling out the tape measures

Interestingly, when we measured the length of our line of bodies outside, we got 3714cm. This led to much discussion about the accuracy of each measurement, how mathematical we had been and which answer to the question was right.